Define "subpoena."

A subpoena is a legal document that compels an individual to appear in court or to produce evidence, such as documents or physical evidence, relevant to a legal proceeding. This instrument serves as an essential tool in the legal system, ensuring that witnesses testify and that necessary evidence is available for trial. The enforceability of a subpoena means that failure to comply can lead to legal consequences, including contempt of court.

The other options do not accurately capture the definition of a subpoena. A request for a dismissal of charges does not represent the function of a subpoena, which instead seeks to gather evidence or testimony. A type of legal opinion refers to a professional evaluation of legal matters and is unrelated to the procedural directive of a subpoena. Lastly, a document that authorizes police action typically pertains to law enforcement directives, such as search warrants, rather than the summons for testimony or evidence represented by a subpoena.